Nginx running on different port on Windows server with IIS on port 80

Question

I have a windows server with IIS running on it with a whole bunch of applications. For one of the application, we need to install Nginx for reverse proxy. We have to call dynamic files from a vendor. Nginx was installed on a different port 8070 since IIS was already on port 80.

The nginx.conf file was updated to reflect a different port. Here is a part of the file that was updated:

server {

    listen      8070;
    server_name localhost;



    location / {
        root   html;
       index  index.html index.htm;
    }

    location /abc/{
    proxy_pass https://my.vendor.com/;
    proxy_set_header Host $host:$server_port;
    proxy_redirect http://localhost/ http://localhost:8070/;
    }

However, when the application tries to access the dynamic files from the vendor, the URL has missing port 8070 and it throws 404 error. I have been playing around the nginx.conf file for days now but still no luck. For the dynamic URL that is generated, if I add the port 8070, there is no issue in accessing the dynamic file from the vendor.

Current URL pattern generated to access the vendor dynamic file. It throws 404 error: http://localhost/abc/VendorDyn.js?load=true&pp=true&mm=false&fptrue&hm=true&er=false

However, it should be as follows with the port number http://localhost:8070/abc/VendorDyn.js?load=true&pp=true&mm=false&fptrue&hm=true&er=false

Is there anything I am missing in the nginx.conf file that will add the port to the URL?

I also tried using the following for the server in the conf file:

 server {       
        listen      localhost:8070;

However, this also didn't help.

Any help or comment will be appreciated. I can;t have Nginx on port 80. I need to have it on a different port than 80.

Thanks.